Buddhism and Hinduism?

Even I am not an expert. As you know Hinduism is a very oldest religion. With time a different kind of beliefs are also added to it. So one of the beliefs is the cast system. This is what i can call it as reason for starting of budhism. In the cast system the peoples are categorised as below Brahmanas- The one who worships the god Kshathriyas- the one who Goes for Fight and rules, E.g. Kings Vaishyas- The one who do business Shoodra- The one who works under vaishyas for daily wages Because of this cast system the large category of Shoodras are frustrated and felt like they need somethings to be changed. At the same time Gauthama Bhudha was spreading his good thoughts like non-violence and peace all over the world many people started following him and these followers with time started budhism and spreading Buddha's thoughts Now a days the cast system is almost extinguished